I think our app is as reactive as a native app despite javascript; if you see any lack of responsiveness I'd be interested in knowing where so I can improve it. I do however agree that it "feels" different on OSX, since you don't have the native animations and look & feel, but I don't think it's related to speed.
Regarding OCaml, using such a strongly typed language enables heavy abstractions without a runtime performance tradeoff, leverages the static optimizer of the OCaml toolchain and outputs optimized javascript (asm like). This is, I would argue, hardly achievable by writing directly plain javascript. Note however that there are other tools that target javascript with similar benefits.
It's not configurable from the Settings screen yet, but you can set the "dashboard-shortcut" key in ~/Library/Application Support/Routine/config.json. In can be any electron accelerator (https://www.electronjs.org/docs/api/accelerator).
Regarding OCaml, using such a strongly typed language enables heavy abstractions without a runtime performance tradeoff, leverages the static optimizer of the OCaml toolchain and outputs optimized javascript (asm like). This is, I would argue, hardly achievable by writing directly plain javascript. Note however that there are other tools that target javascript with similar benefits.